While renovating your email program might seem daunting, it can yield high-impact results that are well worth the time and money spent. The best marketers know how important it is to consistently evaluate—and re-evaluate—email marketing programs. In some cases, even small tweaks to an email program or campaign can return notable outcomes. Here are a few things to take into consideration when evaluating an email marketing program:

Seamless delivery. Smartphones, desktop computers, tablets ... people use them all. Your message needs to look good and function well on various devices if you want it to resonate with your audience. If an email is difficult to read or doesn't load properly, readers are much more likely to hit "delete."

Personalization. Data is good thing, but not if you're drowning in it. Big Data is only effective if it is actionable. Marketing automation can help an email program's efficiency by sending targeted email in real time based on customer behavior and events.

Design. Are your layout and format appealing or just plain stale? While content is of utmost importance, layout and design also play a role in keeping your audience engaged. A design refresh has the potential to give your email marketing program a major upgrade.

User experience. Take a close look at your audience and consider whether your email marketing program is accommodating their needs; for example, consider if links are in the correct places and if there is a quick way to share the email. Also, make sure all email "asks" are straightforward and can be accomplished with ease.

Just because you feel like you've had success with your email refresh, don't dismiss the metrics. As you make changes to your program, take note of which ones yield big dividends and which fall short. It's important to consistently revisit your metrics to see how you've affected conversions and revenue. This is a good way to determine what works for your audience and what doesn't. And don't let the holy grail of perfection get in the way of making iterative improvements today. Ellen Valentine is product evangelist at Silverpop Systems, a marketing automation and email marketing software provider.